#include <bits/stdc++.h>

using namespace std;
#define rep(i,n) for(int i=0;i<n;i++)
#define rep1(i,n) for(int i=1;i<=n;i++)
typedef long long ll;

int main(){
  int n;
  cin >> n;
  int a,b,c,d;
  string r;
  int s[] = {0,1,2,3,4,5,6,7,8,9};
  rep(i,n){
    cin >> a >> b >> c >> d >> r;
    if(r=="YES"){
      rep(j,10){
        if(j!=a && j!=b && j!=c && j!=d){
          s[j] = -1;
          }
        }
      }else{
        s[a] = -1;
        s[b] = -1;
        s[c] = -1;
        s[d] = -1;
    }
  }
  rep(i,10){
    if(s[i]!=-1){
      cout << s[i] << endl;
      return 0;
    }
  }
}